I had my share of bully torture in middle school--being in accelerated math and on the academic team will definitely warrant that. I never thought of myself as a bully. But a friend brought up a story to me when we were explaining our long-running friendship that destroyed my previous notions of behavior.
In fourth grade (yes I started my bullying career young), my best friend Crista and I were in the same class. We did everything together those days. But as she loves to remind me, I wasn't always the nicest friend. I used to make her call me every day before school to inquire as to whether we could be friends that day. Depending on my mood, any previous squabbles, or just because I felt like it, I would say no or yes. A negative response meant she had to sit at another table, not speak or pass notes to me, and could not hang out in my immediate vicinity at recess. More often than not I would say yes, but as Crista reminds me on the days I said no, my reasoning was usually to drag up some dormant argument or to simply say "Because." I was obviously very mature in fourth grade.
Regardless of my targeted bullying, Crista and I have remained the best of friends. I feel like my karmic payback came in the form of the fourth grade presidential election, in which Crista defeated me by a small margin. (However, I still believe the fact that she had passed out animal crackers to the class may have helped a bit). I learned my lesson--bullying was too much work.